' Lander update.bas SmallBASIC 0.12.11 (B+=MGA) 2018-06-01 'modified code from my 2nd mod of: 'Lander mod 2.txt for JB v2 B+ 2018-05-29 big mod of 'Lander by Carl mod Rod mod B+.txt for JB v2 started 2018-05-26 'where I rewired controls and changed physics of Lander Model. 'This will further depart from Carls's original by hand drawing Lander 'at different angles instead of using sprites and, alas, landscape will 'have to be updated each frame because there is no drawing on top of images 'in SmallBASIC. ' INSTRUCTIONS: 'Use the left or right arrow keys to rotate Lander left or right. 'Use the up arrow for thruster burst. These moves cost fuel! 'The Fuel Gage is Red Horizontal line below landscape. 'The fuel level is Yellow. 'You must make a VERY gentle and level landing 'on one of the flat areas! 'Horizontal location, speed in green. ' Vertical location, speed in blue definekey 0xFF04, moveLeft 'press left arrow rotate craft definekey 0xFF05, moveRight 'press right arrow, rotate craft definekey 0xFF09, moveUp 'press up arrow, for forward thrust definekey 27, quit 'press esc to quit const d2r = pi/180 'stars ns = 125 dim sx(ns), sy(ns), sr(ns), sc(ns) for i = 0 to ns sx(i) = rnd * xmax sy(i) = rnd * ymax r = rnd if r < .8 then sr(i) = 1 elif r < .95 sr(i) = 2 else sr(i) = 3 fi sc(i) = rgb(rnd*74 + 180, rnd*74 + 180, rnd*74 + 180) next ' ground profile with flat zones for landing dim terraH(xmax), terraC(xmax) rate1 = rnd / (rnd * 10 + 15) rate2 = rnd / (rnd * 5 + 5) for x = 0 to xmax if x > 0 and rnd < 0.012 then xstop = min(xmax, x + 50) for lz = x to xstop terraH(lz) = y c = rnd * 50 + 50 terraC(lz) = c next x = lz - 1 else holder1 = holder1 + rate1 holder2 = holder2 + rate2 holder3 = holder3 + sin(holder2)/20 y = 600 + sin(holder1) * 50 + cos(holder2) * 50 + cos(holder3) * 15 terraH(x) = y c = rnd * 50 + 50 terraC(x) = c end if next w = window() label restart 'initialize fuel = 500 'this is the space vehicle's fuel 'vda is vehicle degree angle = orientation of the vehicle, mainly it's thrusters vda = 0 'the vehicle is traveling right across screen due East = 0 degrees = 0 Radians speed = 6 'this is the speed the vehicle is moving in the vda direction vx = 50 'this is current x position of vehicle 10 pixles from left side vy = 10 'this is current y position of vehicle 10 pixels down from top of screen 'd stands for delta with stands for change dx = change in x, dy = change in y 'dg is change due to gravity (vertical) 'dat is change of acceleration due to thrust dx = speed * cos(d2r * vda) 'this is the horizontal x change on screen due to speed and angle dy = speed * sin(d2r * vda) 'this is the vertical y change on screen due to speed and angle dg = .1 'this is the constant acceleration gravity applies to the vehicle dat = 2 'this is burst of acceleration a thrust or reverse thrust will apply to speed and angle while 1 cls scene 'fuel line rect 20, ymax - 25, xmax - 20, ymax - 5, 12 filled ff = fuel/500 * (xmax - 40) rect 20, ymax - 20, ff + 20, ymax - 10, 14 filled color 10 at 10, ymax/2 : ? "Horizontal: ";int(vx);", ";int(dx) color 9 at 10, ymax/2 + 20 : ? " Vertical: ";int(vy);", ";int(dy) 'vehicle falls faster and faster, because gravity effects the vertical speed dy = dy + dg 'speed up falling due to gravity acceleration 'new position = last postion plus the horizontal and vertical changes from momentum vx = vx + dx vy = vy + dy if vx < 0 or vx > xmax or vy < -50 then w.alert("You have drifted off screen.") goto playAgain end if if vy <= terraH(vx) and fuel > 0 then Lander vx, vy, d2r * vda else crash\$ = "" if vda <> 270 then crash\$ = crash\$ + "Vehicle not upright. " if dy > 4 then crash\$ = crash\$ + "Came down too fast. " if dx > 4 then crash\$ = crash\$ + "Still moving hoizontally too fast. " if fuel <= 0 then crash\$ = crash\$ + "Ran out of fuel. " if terraH(vx -10) <> terraH(vx + 10) then crash\$ = crash\$ + "Did not land on level site. " if crash\$ <> "" then w.alert(crash\$, "You crashed!") else w.alert("Nice job!", "Successful landing!") end if goto playAgain end if showpage delay 100 wend label playAgain w.ask("", "Play Again?") if w.answer = 0 then goto restart stop sub scene for i = 0 to ns circle sx(i), sy(i), sr(i), 1, sc(i) filled next for i = 0 to xmax line i, terraH(i) , i, ymax, rgb(terraC(i), terraC(i), terraC(i)) next end ' arrow + esc key sub moveUp 'here is the vertical and horizontal change from a burst of fuel for thrust thrustx = dat * cos(d2r * vda ) thrusty = dat * sin(d2r * vda ) 'now change the horizontal and vertical momentums from the thrust dx = dx + thrustx dy = dy + thrusty 'update the position vx = vx + dx vy = vy + dy circle vx, vy, 5, 1, 14 filled showpage 'the thrust cost fuel fuel = fuel - 10 end sub moveLeft local x1, y1 x1 = vx + 10 * cos(d2r * vda + .5 * PI) y1 = vy + 10 * sin(d2r * vda + .5 * PI) circle x1, y1, 5, 1, 14 filled showpage vda = vda - 22.5 if vda < -0.01 then vda = 360 fuel = fuel - 10 end sub moveRight local x1, y1 x1 = vx + 10 * cos(d2r * vda - .5 * PI) y1 = vy + 10 * sin(d2r * vda - .5 * PI) circle x1, y1, 5, 1, 14 filled showpage vda = vda + 22.5 if vda > 337.51 then vda = 0 fuel = fuel - 10 end sub quit stop end sub Lander(x0, y0, rAngle) 'rebuilt from ground up literally! 'x0, y0 are at the base of the lander, the rocket will point rAngle up when landing local pangle, x1, x2, y1, y2, x3, y3, x4, y4, i, arr color rgb(195, 195, 225) x1 = x0 + 10 * cos(rAngle - .5 * PI) y1 = y0 + 10 * sin(rAngle - .5 * PI) x2 = x0 + 10 * cos(rAngle + .5 * PI) y2 = y0 + 10 * sin(rAngle + .5 * PI) x3 = x0 + 10 * cos(rAngle) y3 = y0 + 10 * sin(rAngle) x4 = x0 + 25 * cos(rAngle) y4 = y0 + 25 * sin(rAngle) 'legs/fins line x3, y3, x1, y1 line x3, y3, x2, y2 line x4, y4, x1, y1 line x4, y4, x2, y2 x5 = x0 + 20 * cos(rAngle) y5 = y0 + 20 * sin(rAngle) pangle = 2 * pi / 8 dim arr(2 * 8 + 1) for i = 0 to 8 x1 = x4 + 15 * cos(i * pangle + rAngle) y1 = y4 + 15 * sin(i * pangle + rAngle) arr(2 * i) = x1 arr(2 * i + 1) = y1 next drawpoly arr filled end